App permissions
Application Access
The Cloud Connect apps communicate through a special “app user” with the Jira, and this app user will be the member of the “atlassian-addons-admin”, “jira-users” and “jira-software-users” groups after installation by default. Due to this, the app user will have Application access in the instance.
Removing this special addon group, or modifying the default access groups is not recommended, and can casue well known issues with addons, eg.:
https://community.developer.atlassian.com/t/add-on-user-permissions-problem/48760
https://confluence.atlassian.com/jirakb/unable-to-install-any-cloud-add-ons-971608404.html
Make sure, that the default access groups are in place or if you change them to newly created ones, install the app after the changes, and grant Jira product access to these newly created groups.
Global permissions
Browse Users and Groups. Make sure that the Atlassian Add-On Administrator group (atlassian-addons-admin) has the Browse Users permission in the JIRA Global Permissions.
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